Hi,
we're currently working on a project that is connected to a CCHP plant. HVAC thermal needs (cooling and heating) are supplied by the referred plant. Due to this, in terms of energy performance calculations, we need to take into account:
- Ratio of total CCHP gas consumption that is associated with building thermal needs. This will be accounted as a gas cost;
- Ratio of total CCHP electricity production that is associated with building thermal needs. This electricity will be subtracted to proposed electricity needs.
Thinking of energy simulation report (and also LEED templates), how shall we deal with this? Do you think that leaving HVAC - cooling and HVAC - heating fields blank at energy simulation report and then upload an exceptional calculation narrative (to support gas cost and electricity production) can be an acceptable strategy?
Any suggestions?
Regards,
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5907 thumbs up
January 22, 2019 - 11:23 am
The best way to report this would be to show the heating and cooling consumption without the CCHP plant. Then show the natural gas consumption of the plant, the electric production of the plant, and the space heating/space cooling related energy production in an exceptional calculation. The last three items would obviously be subtracted. Make sure you explain how the calculations were derived in your exceptional calculation narrative.
You could also probably skip the exceptional calculation and just report the gas consumption, electric production, and thermal production. The last item could be shown by zeroing out the space heating/cooling energy use. If you do this make sure you provide a narrative and calculations demonstrating that the CCHP thermal production will exceed the building's thermal consumption.